"I know they will be some in Brisbane today asking 'why is this necessary? There is only one case. '" said Prime Minster Scott Morrison.
"Well, this isn't any ordinary case.
"This is a very special case and one that requires us to treat things quite differently until we know more and we will learn much in the next few days.
"What Queenslanders will be doing over the next few days, they will be doing not just for themselves and their own communities, but for the rest of the country.
"So again, I thank you for the patience you will have to show in relation to disruption, we know it causes disruption. But we're also quite short that it is the prudent course action given the circumstances.
Photo ABC News